React Native Media Queries

This module brings media queries like functionality to React Native styles.
Uses React.Dimensions.get('window') (or the nativeEvent data when bound to onLayout) to determine width and height of the screen.

Install

npm install react-native-media-queries

Quick Start

If you want to write this:

/* This is of course CSS, don't paste it in your RN app, you fool! */
.logo {
  height: 200px;
}

@media (max-height: 500px) {
  .logo {
    height: 120px;
  }
}

Write this instead:

import { createStyles, maxHeight } from 'react-native-media-queries';

// Define your styles
const base = {
  logo: {
    height: 200
  }
};

const styles = createStyles(
  base,

  // override styles only if screen height is less than 500
  maxHeight(500, {
    logo: {
      height: 120
    }
  })
);

Then use styles in your components as you're already used to, i.e. <Logo style={styles.logo} />.

API

maxHeight(height, styles)

Equivalent to max-height in CSS. Apply styles only if screen height is less than or equal height.

minHeight(height, styles)

Equivalent to min-height in CSS. Apply styles only if screen height is greater than or equal height.

maxWidth(width, styles)

Equivalent to max-width in CSS. Apply styles only if screen width is less than or equal width.

minWidth(width, styles)

Equivalent to min-width in CSS. Apply styles only if screen width is greater than or equal width.

aspectRatio(ratio, styles)

Equivalent to aspect-ratio in CSS. Apply styles only if the aspect ratio of the screen is the same as the ratio provided.
Note: Ratio must be in the form 16/9.

maxAspectRatio(ratio, styles)

Equivalent to max-aspect-ratio in CSS. Apply styles only if the aspect ratio of the screen is less or equal than the ratio provided.

minAspectRatio(ratio, styles)

Equivalent to min-aspect-ratio in CSS. Apply styles only if the aspect ratio of the screen is greater or equal than the ratio provided.

createStyles(baseStyles, expression1, expression2...)

Start from baseStyles and apply further matching expressions.

Compose expressions

Expressions are composable meaning you can apply a certain style only if the screen height is greater than X AND less than Y (for example).

Basically, if you want something like this @media (min-height: 500px) and (max-height: 1200px), you'd write this instead:

const base = {
  logo: {
    height: 200
  }
};

const styles = createStyles(
  base,

  // override styles only if screen height is greater than 500 and less than 1300
  minHeight(500, maxHeight(1300, {
    logo: {
      height: 120
    }
  }))
);

And you can have multiple expressions too:

const base = {
  logo: {
    height: 200
  }
};

const exp1 = {
  logo: {
    borderWidth: 5
  }
};

const exp2 = {
  logo: {
    backgroundColor: '#ddd'
  }
};


const styles = createStyles(
  base,
  minHeight(500, exp1),
  minWidth(750, exp2)
);

React (ahahah :/) to screen orientation changes / window resize

As of version 0.1.0 it is possible to update styles whenever the dimensions of the screen change, achieving a closer media queries implementation to what is available with CSS on the web.

A function onLayout is provided in the object returned from createStyles() (eg. styles.onLayout). You will need to call this function everytime your root component updates its layout, so you'll have to bind it to the component's onLayout prop.

class MyComponent {
  render() {
    return (
      <View onLayout={styles.onLayout()}>
        <Text style={styles.title}>YO mama</Text>
      </View>
    );
  }
}

const base = {
  title: {
    fontSize: 16
  }
};

const biggerFont = {
  title: {
    fontSize: 20,
    backgroundColor: 20,
  }
};


const styles = createStyles(
  base,
  minHeight(500, biggerFont),
);

NOTE: This example, as is, will not work because React does not re render the interface unless the state or the props have been updated. You can force a component to re render (even if it's not encouraged), so that this module actually works. It's a bit of a hack but depending on your situation it might be the only way to have the styles update on orientation changes / window resize. You can pass a callback to onLayout, it will get fired only if the styles have changed.

Here's how you would use forceUpdate to force a re render and make the previous example work:

class MyComponent {
  render() {
    return (
      <View onLayout={styles.onLayout(() => this.forceUpdate())}>
        <Text style={styles.title}>YO mama</Text>
      </View>
    );
  }
}

const base = {
  title: {
    fontSize: 16
  }
};

const biggerFont = {
  title: {
    fontSize: 20,
    backgroundColor: 20,
  }
};


const styles = createStyles(
  base,
  minHeight(500, biggerFont),
);

Changelog

0.3.0

Introduce aspectRatio queries.

0.1.0

Introduce onLayout callback and reactive updates to window size changes.
Thanks to Quincy Mitchell for providing feedback and testing on Windows :)

License

Copyright (c) 2016, Marco Sampellegrini [email protected]

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.